"What if" extra credit blog

"What would happen if everyone on earth stood as close to each other as they could and jumped, everyone landing on the ground at the same instant?"

The logistics of getting all the people on the Earth in one spot is almost impossible. So to start this scenario, entire Earth’s population has been magically transported together into one place. A crowd of all the people in the Earth standing as close together as possible would take up an area the size of Rhode Island.

Then, somehow, if everyone jumped and landed all at the exact same time...

...nothing would happen.

Earth outweighs the people on it by a factor of over ten trillion. On average, humans can vertically jump maybe half a meter on a good day. Even if the Earth were rigid and responded instantly, it would be pushed down by less than an atom’s width.

Technically, this delivers a lot of energy into the Earth, but it’s spread out over a large enough area that it doesn’t do much. However, the sound of everyone's feet hitting the ground at the same time could create a loud roar which would last many seconds.

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LSA E Mech 2017-18

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